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Pituitary adenylate cyclase-activating polypeptide (PACAP, ADCYAP1: adenylate cyclase-activating polypeptide 1), a neuropeptide with neurotransmission modulating activity, is a promising schizophrenia candidate gene. Here, we provide evidence that genetic variants of the genes encoding PACAP and its receptor, PAC1, are associated with schizophrenia. We studied the effects of the associated polymorphism in the PACAP gene on neurobiological traits related to risk for schizophrenia. This allele of the PACAP gene, which is overrepresented in schizophrenia patients, was associated with reduced hippocampal volume and poorer memory performance. Abnormal behaviors in PACAP knockout mice, including elevated locomotor activity and deficits in prepulse inhibition of the startle response, were reversed by treatment with an atypical antipsychotic, risperidone. These convergent data suggest that alterations in PACAP signaling might contribute to the pathogenesis of schizophrenia.Molecular Psychiatry (2007) 12, 1026–1032; doi:10.1038/sj.mp.4001982; published online 27 March 2007 [ABSTRACT FROM AUTHOR]

We examined, for the first time, the possible association between schizophrenia and the anaplastic lymphoma kinase (ALK) gene which plays an important role in neurodevelopment. When two nonsynonymous polymorphisms (Arg1491Lys and Glu1529Asp) were examined, there were significant differences in genotype and allele distributions between patients and controls. Individuals homozygous for the minor allele (1491Lys–1529Asp) were more common in patients than in controls (p = 0.0064, odds ratio 2.4, 95% CI 1.3–4.6). These results suggest that genetic variations of the ALK gene might confer susceptibility to schizophrenia. [ABSTRACT FROM AUTHOR]

Acquired ileal diverticulum is an uncommon condition and diagnosis is often difficult when bleeding occurs from this source. Here we describe two cases of ileal diverticulum with massive bleeding. Both patients presented with anal bleeding, but upper and lower gastrointestinal endoscopy did not reveal the source. Selective visceral angiography finally detected bleeding lesions in the terminal ileum. Surgical resection was performed in both patients, confirming that the bleeding arose from diverticula less than 1 cm in size. In patients with obscure gastrointestinal bleeding, an ileal diverticulum should be considered, and selective visceral angiography should be performed for precise diagnosis. [ABSTRACT FROM AUTHOR]

The lysosomal membrane encloses numerous hydrolytic enzymes and prevents the cytoplasm from being damaged by these enzymes. It is possible that the fragility of this membrane may be implicated in the pathogenesis of gastric mucosal damage. We investigated the effects of 16,16-dimethyl prostaglandin E2 (dmPGE2), which is known to protect the gastric mucosa from various noxious agents, on lysosomal membrane stability in the rat stomach. Sodium taurocholate (TC) was used as the damaging agent. To assess lysosomal membrane stability in the gastric mucosa, we assayed acid phosphatase released from lysosomes isolated from a gastric mucosal homogenate. To assess lysosomal membrane stability in gastric surface epithelial cells, we used laser scanning confocal microscopy to observe the fading of red fluorescence in living cells vitally stained with acridine orange. Exogenous dmPGE2 enhanced lysosomal membrane stability in the gastric mucosa, whereas TC decreased it. In gastric surface epithelial cells, exogenous dmPGE2 protected the cells against TC-induced damage and prevented TC-induced decreased lysosomal membrane stability. It was concluded that a decrease in lysosomal membrane stability seemed to be closely involved in the pathogenesis of gastric mucosal damage. Moreover, it appears that stabilization of the lysosomal membrane by exogenous dmPGE2 may contribute to its protective effect in the gastric mucosa, both at the level of gastric surface epithelial cells and in regard to the entire gastric mucosa. [ABSTRACT FROM AUTHOR]

Distribution of microtubules and other cytoskeletal filaments in growing skeletal muscle cells (myotubes) was studied in vitro by fluorescence microscopy using fluorescin-labeled antibodies and phalloidin, a specific antiactin drug. In the distal elongating tips of myotubes, microtubules were the major cytoskeletal elements; actin and intermediate filaments were much less abundant. On the other hand, colcemidand nocodozole-treatments caused disruption of microtubules and also prompt retraction of growth tips to form myosacs, a type of deformed myotube. Actin filaments remained unaffected during the retraction. The difference in the distribution of the 3 cytoskeletal filaments in the region of growth tips was most remarkable in the case of those myotubes in the process of recovery from myosacs. In an early phase of recovery, the cellular processes extending from myosacs were enriched with both microtubules and intermediate filaments, but not with actin filaments. Later, when the processes became further developed, intermediate filaments were scarce at the extreme ends. Fluorescein-labeled actin introduced by a micro-injection method was minimally incorporated into filaments in the cellular processes. We conclude that microtubules make up the cytoskeletal element which is most responsible for elongation or spreading of growth tips of myotubes in vitro. [ABSTRACT FROM AUTHOR]